Merge pull request #5718 from ctiller/dns_retry

Dns retry support

1 files changed, 148 insertions, 0 deletions

diff --git a/test/core/client_config/resolvers/dns_resolver_connectivity_test.c b/test/core/client_config/resolvers/dns_resolver_connectivity_test.c
new file mode 100644
index 0000000000..75d1eb674f
--- /dev/null
+++ b/test/core/client_config/resolvers/dns_resolver_connectivity_test.c
@@ -0,0 +1,148 @@
+/*
+ *
+ * Copyright 2015-2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "src/core/client_config/resolvers/dns_resolver.h"
+
+#include <string.h>
+
+#include <grpc/grpc.h>
+#include <grpc/support/alloc.h>
+
+#include "src/core/iomgr/resolve_address.h"
+#include "src/core/iomgr/timer.h"
+#include "test/core/util/test_config.h"
+
+static void subchannel_factory_ref(grpc_subchannel_factory *scv) {}
+static void subchannel_factory_unref(grpc_exec_ctx *exec_ctx,
+                                     grpc_subchannel_factory *scv) {}
+static grpc_subchannel *subchannel_factory_create_subchannel(
+    grpc_exec_ctx *exec_ctx, grpc_subchannel_factory *factory,
+    grpc_subchannel_args *args) {
+  return NULL;
+}
+
+static const grpc_subchannel_factory_vtable sc_vtable = {
+    subchannel_factory_ref, subchannel_factory_unref,
+    subchannel_factory_create_subchannel};
+
+static grpc_subchannel_factory sc_factory = {&sc_vtable};
+
+static gpr_mu g_mu;
+static bool g_fail_resolution = true;
+
+static grpc_resolved_addresses *my_resolve_address(const char *name,
+                                                   const char *addr) {
+  gpr_mu_lock(&g_mu);
+  GPR_ASSERT(0 == strcmp("test", name));
+  if (g_fail_resolution) {
+    g_fail_resolution = false;
+    gpr_mu_unlock(&g_mu);
+    return NULL;
+  } else {
+    gpr_mu_unlock(&g_mu);
+    grpc_resolved_addresses *addrs = gpr_malloc(sizeof(*addrs));
+    addrs->naddrs = 1;
+    addrs->addrs = gpr_malloc(sizeof(*addrs->addrs));
+    addrs->addrs[0].len = 123;
+    return addrs;
+  }
+}
+
+static grpc_resolver *create_resolver(const char *name) {
+  grpc_resolver_factory *factory = grpc_dns_resolver_factory_create();
+  grpc_uri *uri = grpc_uri_parse(name, 0);
+  GPR_ASSERT(uri);
+  grpc_resolver_args args;
+  memset(&args, 0, sizeof(args));
+  args.uri = uri;
+  args.subchannel_factory = &sc_factory;
+  grpc_resolver *resolver =
+      grpc_resolver_factory_create_resolver(factory, &args);
+  grpc_resolver_factory_unref(factory);
+  grpc_uri_destroy(uri);
+  return resolver;
+}
+
+static void on_done(grpc_exec_ctx *exec_ctx, void *ev, bool success) {
+  gpr_event_set(ev, (void *)1);
+}
+
+// interleave waiting for an event with a timer check
+static bool wait_loop(int deadline_seconds, gpr_event *ev) {
+  while (deadline_seconds) {
+    gpr_log(GPR_DEBUG, "Test: waiting for %d more seconds", deadline_seconds);
+    if (gpr_event_wait(ev, GRPC_TIMEOUT_SECONDS_TO_DEADLINE(1))) return true;
+    deadline_seconds--;
+
+    grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+    grpc_timer_check(&exec_ctx, gpr_now(GPR_CLOCK_MONOTONIC), NULL);
+    grpc_exec_ctx_finish(&exec_ctx);
+  }
+  return false;
+}
+
+int main(int argc, char **argv) {
+  grpc_test_init(argc, argv);
+
+  grpc_init();
+  gpr_mu_init(&g_mu);
+  grpc_blocking_resolve_address = my_resolve_address;
+
+  grpc_resolver *resolver = create_resolver("dns:test");
+
+  grpc_client_config *config = (grpc_client_config *)1;
+
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  gpr_event ev1;
+  gpr_event_init(&ev1);
+  grpc_resolver_next(&exec_ctx, resolver, &config,
+                     grpc_closure_create(on_done, &ev1));
+  grpc_exec_ctx_flush(&exec_ctx);
+  GPR_ASSERT(wait_loop(5, &ev1));
+  GPR_ASSERT(config == NULL);
+
+  gpr_event ev2;
+  gpr_event_init(&ev2);
+  grpc_resolver_next(&exec_ctx, resolver, &config,
+                     grpc_closure_create(on_done, &ev2));
+  grpc_exec_ctx_flush(&exec_ctx);
+  GPR_ASSERT(wait_loop(30, &ev2));
+  GPR_ASSERT(config != NULL);
+
+  grpc_client_config_unref(&exec_ctx, config);
+  GRPC_RESOLVER_UNREF(&exec_ctx, resolver, "test");
+  grpc_exec_ctx_finish(&exec_ctx);
+
+  grpc_shutdown();
+  gpr_mu_destroy(&g_mu);
+}